Implement visit_ListComp()

[Smit-create]

Python code:

def f(x: list[i32]):
    y: list[i32]
    k: i32
    y = [2*x[k] for k in range(len(x))]

ASR:

LFortranException: visit_ListComp() not implemented

[Smit-create]

Another issue
Python code:

def f():
    x: list[i32]
    x = [1,2,3]
    x.append(5)
    print(x)

ASR:

semantic error: Only Name supported in Call
 --> expr.py:4:5
  |
4 |     x.append(5)
  |     ^^^^^^^^^^^ 

[Thirumalai-Shaktivel]

How should we handle this?
Create a new node, say: "ListComp" or create a new ASR pass?
@czgdp1807